1. Field of the Invention
This invention relates to a wireless communication device which, for example, constitutes a network among a plurality of wireless communication devices.
2. Description of the Related Art
In recent years, a method of connecting wireless communication devices to personal computers or similar equipment and constructing a wireless local area network (LAN) among a plurality of personal computers has been widely known as one method of connecting a plurality of personal computers as a LAN.
In such a wireless LAN of the prior art, in order to recognize the wireless communication devices and equipment connected to the wireless network, a method has conventionally been employed in which the equipment units actually connected are displayed on a monitor of personal computers and similar that are connected to the network to enable users to visually verify the equipment.
In other words, a method has been used in which, when transferring data of some kind to equipment connected to the wireless network, the equipment connected to the network is verified on the monitor of the personal computer or similar of the apparatus that is the sender of the information, the destination equipment is specified, and the information is transferred.
On the other hand, recently there have been increases in the transmission capacities of wireless LANs, and methods are being considered in which audio and video equipment (hereafter “AV equipment”) is incorporated into wireless networks for wireless transmission.
In the past, there has been widely used a video transmission method of AV equipment, in which the output terminals of such equipment and the input terminals of monitor apparatuses are connected by connecting cords, and by switching the input of the monitor apparatus, desired video information is displayed.
Further, methods are being considered for the exchange of data by constructing, in a communication area over shorter distances than such a wireless LAN, personal area networks (PANs) centered on portable devices and equipment owned by an individual.
In such a PAN, it is assumed that in addition to a personal computer, consumer equipment such as a camcorder, a VCR (videocassette recorder) apparatus, and a monitor will also be incorporated in the network.
In such a wireless PAN, the exchange of authentication information in advance between devices has been required in order to recognize the wireless communication devices and equipment connected to the wireless network.
For example, in a wireless PAN conforming to the IEEE 802.15.3 communication standard, an operation that is called “authentication” is stipulated, and a device which has executed “association” with the PAN is supposed to exchange encoded information and other device link information with other devices.
As the method of exchanging device link information, a method is conventionally employed in which information is exchanged as one link in both directions between the two devices.
An application previously filed by this applicant is Japanese Patent Application No. 2001-289763. According to this prior application, in order to effect peer-to-peer operation between a transmission device and a receiving device, a transmission device identification number (ID) is registered in advance with the receiving device.
However, when AV equipment is connected to a conventional wireless network as described above, there is a disadvantage that some kind of monitor device or other display functions must be added to the AV equipment from which information is to be sent, in order to specify the monitor device which is to be the destination.
In order to resolve the above disadvantage, there has been required such complicated processing as: equipment connected to the wireless network is displayed on a monitor device side, and based on this display a user selects a device whose monitor performs display; and thereafter information is transmitted to the device.
In a conventional video transmission method using AV equipment, input switching on the monitor device side can be performed simultaneously with display of information input to the device terminals, so that the user need not perform complicated operations; however, when wireless transmission over a wireless LAN is performed, the above-described complex input selection processing is required, and so there is an inconvenience for a user.
Further, in conventional authentication operations, if processing is not performed between devices on which the same application is installed, exchange of the device link information necessary for such communications is not possible, and so there is the problem that data cannot be exchanged.
That is, when data is transmitted and received between connected devices the applications of which are different, it is not possible for either device to judge what kind of data is being sent, and so there is the problem that data transmission itself is useless.
Moreover, if device link information cannot be exchanged between devices intended for communication by the user, there is a possibility that an ill-intended device may be incorporated into the wireless network and may disseminate personal information to an unauthorized device.
Consequently there is the disadvantage that this authentication operation requires the exchange of device link information only by devices approved by a wireless network user with devices associated with the wireless network.
In a wireless PAN conforming to the IEEE 802.15.3 communication standard, during standardized authentication operations, an operation is required in which the wireless communication devices for which authentication operation is to be initiated are specified.
Further, in conventional authentication operations, emphasis was placed mainly on the construction of wireless networks between computer systems, so that authentication has been performed by devices which input and output data exchanged between applications, without particular consideration paid to the direction in which data is sent.
Consequently if authentication operation with an ill-intended device succeeds, and the device is incorporated into the network, there is the problem that content not intended for dissemination by the user may easily be disseminated or viewed by others.
There is the further problem that a computer virus or other ill-intended content can be sent into the network.
This invention was devised in light of these problems, and an object of the present invention is to provide a wireless communication device and wireless communication method which, through a simplified input/output switching operation, can switch wireless transmission between a plurality of wireless communication devices.
For example, one object is to realize a method to obtain desired information from a wireless transmission channel through simple input switching operations by a user, with respect to a plurality of equipment units connected to monitor devices.
Further, in light of the above problems, this invention has as an object of providing wireless communication devices which constitute a secure wireless network by exchanging device link information between devices operating the same application intended by users.
A further object is to provide a wireless communication method of exchanging device link information between devices intended by users through simple operations.
Another object is to provide a wireless communication method with which, even when an ill-intended device is authenticated by the network, content that is not intended to be disseminated by a user cannot easily be extracted.